Currently, facing with various limitations presented by traditional die blanking lines, a steel machining centre or an entire car plant has an urgent need for a flexible blanking line which reduces costs in the design, fabricating, storage and maintenance of dies, shortens the research and fabricating time, such as the die development and test period, and also meets the increasing market demand on new vehicle models and small-batch personalized vehicle models.
In Chinese patent application No. CN102105256, at least two movable door frames and at least one movable laser cutting head for each portal frame are provided for cutting by moving in a transverse or longitudinal direction, and during the cutting, a plate strip is moved, and the cutting head moves along with the plate strip to perform dynamic cutting; in this way a production yield close to that with a conventional blanking line can be achieved. However, in the case of such a plate strip movement, it is difficult to ensure alignment of transverse or longitudinal cuts generated by multiple moving cutting heads during the movement of the plate strip; and there are also some technical difficulties such as in achieving follow-up movement of a laser cutting head in a dynamic high-speed cutting operation.
Chinese patent application No. CN03811400 discloses a laser cutting device, a laser cutting method and a laser cutting system, wherein two telescopic belt conveying mechanisms are used in a cutting region to feed and receive materials, during which intermittent cutting is done, thereby avoiding damage to the parts and achieve dust absorption, with recycling of waste materials left from the cutting being done downstream of the cutting device. This patent also discloses an embodiment comprising a material delivery device, a machining head, a head moving device, and an upstream and a downstream side support device. By way of branched output or by supplying laser rays to two machining head differently in terms of time, one machining head performs an edge cutting operation upstream of a pinch roller, and the other machining head performs a sheet cutting operation in a cutting region. The machining heads between two belt conveying mechanisms inevitably comes into direct cutting contact with the belts in the cutting region, thus affecting the detection and replacement of the conveying belts, and affecting continuous production by the system; at the same time, there is also a possibility for small waste material pieces to fall from the cutting region.
This patent (Patent Application No. CN03811400) is based on increased material utilization resulting from laser cutting, and has many advantages such as strong adaptation to sheet thickness and width, elimination of the need of specialized dies, and great simplification of the production line. However, there exists a conflict between the requirements on high speed and high yield of the production line and the requirements on reliable cutting quality and smooth removal of wastes, which conflict remains a technical difficulty when applying high-speed laser cutting to material machining.